Now, I'm not a golfer, but I am a frequent walker. There is much debate as to whether or not Mark Twain was responsible for the following quotation:
Golf is a good walk spoiled.But regardless of who actually provided us with this gem, I'm firmly in agreement with it. To me, it just seems like groups of people going for long walks through stupendously manicured parks, pausing occasionally to hit a small white ball with a metal stick. The fact that if you're particularly good at it (the hitting the small white ball part that is, you don't actually have to be particularly good at the walking part), you can earn staggering amounts of money does, I suppose, explain some of its appeal.
The one thing I do know about golf is that under par is good, whereas over par is not so good. In fact, the whole point, if there is a point, is to hit the small white ball as few times as possible so that you can be as far under par as you can.
So, why is it that outside this particular pass-time, the meaning is reversed? An under par performance, usually means a poor performance; if I say I'm feeling a little below par, it means that I'm not feeling 100%. Common usage is the exact opposite of what the term actually means.
Another term from the sporting vernacular is to describe something surprising as "having come out of left field". This term originates from the sport of baseball (a sport of which I know almost as much about as golf, despite it being broadly similar to the school-ground game of rounders).
Again, however, the common usage is actually incorrect. Since the majority of humans (and hence baseball players) are right-handed, the natural tendency is to hit the ball towards the batting player's left (i.e. 'the left field'), as the image above illustrates (the one with the baseball player, not the golf ball). As such, a ball being returned from left field is actually pretty common. It's the ones that come out of right field that actually cause more consternation because they happen a lot less frequently.
Again, as in the previous example, the term is used in a way that is entirely at odds with the original meaning when applied to the sport from which the term was derived.
I could probably go on, but I suspect the resounding response from anyone who isn't particularly interested in linguistic origins would probably be, "Well, so what?" I do wonder sometimes, however, if anyone ever stops and thinks about some of the expressions they use in daily speech.